Diffuse skin findings secondary to lymph node tularemia in a patient with chronic rheumatoid arthritis on methotrexate.

Tularemia has many atypical presentations which can represent a diagnostic challenge. The history is essential in the investigation of this disease. Bite-induced primary skin lesions should be distinguished from the infrequent immune-mediated secondary skin lesions. Herein, we present an atypical pseudovesicular rash secondary to Francisella tularensis.

Spontaneous decolonization during hospitalization in intensive care unit patients colonized by extended-spectrum beta-lactamase-producing Enterobacterales.

This study aimed to analyse the frequency of occurrence of spontaneous decolonization in intensive care unit patients colonized by extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-E) in order to assess the added value of continuing weekly ESBL-E rectal carriage screening in these patients. In total, 49,468 weekly rectal screening samples taken from 20,846 patients over 12 years were included. Among the 4280 ESBL-E carriers, only 109 patients (2.5%) could be considered decolonized at the end of their hospitalization with at least three consecutive negative samples. Overall, 7957 samples (16.1%) were requested for patients already identified as ESBL-E carriers. Avoiding unnecessary weekly screening following positive ESBL-E colonization results could decrease nursing and laboratory work loads.

A case of bacteriemic mediastinitis due to Prevotella buccae after cardiac surgery.

Mediastinitis is a well-known complication of open-heart surgery. Strictly anaerobic bacteria are rarely found in this condition, unlike in descending mediastinitis. We report the case of a mediastinitis due to Prevotella buccae after surgical replacement of the aortic valve and triple coronary artery bypass in an immunocompetent 76 year-old man. The bacteria were found in pure culture on blood samples and surgical samples. This case emphasizes the need to perform anaerobic cultures in case of sternal wound infection after open-heart surgery.

Daptomycin versus Vancomycin as Post-Operative Empirical Antibiotic Treatment for Prosthetic Joint Infections: A Case-Control Study.

Purpose: To compare safety and efficacy of Vancomycin (Van) versus Daptomycin (Dap) as post-operative empirical antibiotic treatment (PEAT) in patients with periprosthetic joint infections (PJIs). Methods: Medical charts of patients treated empirically with Van or Dap in the post-operative period of total hip/knee prosthesis septic revision until the results of intra-operative culture were reviewed. Cefotaxime, cefepime or aztreonam were used in combination with Dap or Van. Results: Twenty Dap patients were matched with 20 other Van patients according to the age and type of prosthesis. The ASA score and the distribution of the pathogens was similar in the two groups especially regarding the number of methicillin-resistant staphylococci. The mean duration of the PEAT was 6.07 ± 0.85 days. A total of 17 episodes of adverse events (AE) in 10 patients (25%) were recorded during the PEAT which led to discontinue the treatment in 5 patients, all of them treated with Van (P=0.02). At the end of a mean post-treatment follow-up of 618 +/- 219 days, 36 patients remained in remission of infection; 2 patients failed in each group. Conclusions: Our observations suggest that PEAT with Van for septic revision of PJIs is associated with a higher discontinuation rate due to AE but with a similar outcome than it is with Dap.

In vitro activity of temocillin against extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae strains isolated from urinary tract infections in France.

OBJECTIVES: Temocillin was introduced in 2015 in the French guidelines for the treatment of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae urinary tract infections. Little susceptibility data is available. We investigated the in vitro activity of temocillin against ESBL-producing Enterobacteriaceae isolated from samples of cytobacteriological examinations of urine. MATERIAL AND METHODS: Susceptibility testing was performed on 157 ESBL-producing E. coli and 95 ESBL-producing K. pneumoniae strains using the disk diffusion method. MICs of resistant strains were measured with the Etest method. RESULTS: Using current breakpoints, 71.3% of E. coli strains and 77.9% of K. pneumoniae strains were classified as susceptible. However, diameter and MIC breakpoints vary by country, and we reported discordance of clinical categorization between diameters and MIC determination for some strains. The measure of diameters was also sometimes difficult because of contaminating colonies within the inhibition zone. CONCLUSION: We highlighted difficulties related to the determination of temocillin susceptibility, such as culture of resistant colonies in the inhibition zone and discordance of clinical categorizations obtained with the disk diffusion method or the Etest method. Overall, 42% of tested Enterobacteriaceae had a diameter or MIC close to the current breakpoints; thus, it is necessary to determine the MIC for these strains before considering the clinical use of this molecule.

Diagnostic accuracy of the alpha defensin lateral flow device (Synovasure) for periprosthetic infections in microbiologically complex situations: A study of 42 cases in a French referral centre.

BACKGROUND: Joint aspiration is currently the reference standard test for diagnosing periprosthetic joint infection (PJI) despite the high rate of false-negative results, of which a major cause is the fastidious nature of some microorganisms. A rapid diagnostic test that detects alpha defensin (Synovasure™, Zimmer, Warsaw, IN, USA) in joint fluid can provide the diagnosis of PJI within a few minutes across the full spectrum of causative organisms (including mycobacteria and yeasts). Its performance in detecting bacterial infections is unaltered by concomitant antibiotic therapy. Few studies of Synovasure™ have been conducted by groups that were involved in designing the test, which has not been validated in France. Assessments in referral centres where complex microbiological situations are common hold considerable interest. The objective of this prospective study was to determine the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and causes of error of Synovasure™ used to diagnose periprosthetic infection in complex microbiological situations. HYPOTHESIS: The rapid diagnostic test Synovasure™ has greater than 90% NPV for detecting periprosthetic infections in complex microbiological infections. MATERIAL AND METHODS: Synovasure™ was used 42 times in 39 patients between October 2015 and October 2017 in challenging microbiological situations [discordant joint aspiration results (n=20), negative cultures with clinical or laboratory evidence of infection, (n=21), and concomitant antibiotic therapy (n=1)]. Of the 39 patients, 23 had total knee prostheses, 13 total hip prostheses, and 3 total femoral prostheses. The reference standard to which the Synovasure™ results were compared was the PJI criteria set developed by the Musculoskeletal Infection Society (MSIS). RESULTS: Synovasure™ was negative in 30 cases with negative joint fluid cultures (30/42, 71.4%). Of the 12 (28.6%) cases with positive Synovasure™ results, only 7 (7/12, 58.3%) had positive joint fluid cultures. According to the MSIS criteria 9 cases were infected, including 8 with positive and 1 with negative Synovasure™ results. Of the 33 cases that were not infected according to MSIS criteria, 29 had negative and 3 positive Synovasure™ results; the remaining case had a positive Synovasure™ result but was excluded when metallosis was found intra-operatively. NPV was 96.7%, PPV 72.7%, sensitivity 88.9%, and specificity 90.6%. DISCUSSION: The high NPV of Synovasure™ suggests a role for this test in microbiologically complex situations as a new tool for ruling in and, most importantly, ruling out infection in doubtful cases. LEVEL OF EVIDENCE: III, prospective study of diagnostic accuracy.

Suppressive antibiotic therapy with oral tetracyclines for prosthetic joint infections: a retrospective study of 78 patients.

PURPOSE: This study aimed at describing the use of oral cyclines (i.e., doxycycline and minocycline) as suppressive antibiotic therapy (SAT) in patients with periprosthetic joint infections (PJIs). METHODS: Medical charts of all patients with surgical revisions for PJIs who were given cycline-based SAT because of a high failure of various origins were reviewed. Data regarding tolerability and effectiveness of cycline-based SAT were analysed. RESULTS: Seventy-eight patients of mean age 64 ± 17 years received cycline-base SAT in the period from January 2006 to January 2014. PJIs involved the knee in 37 patients (47%), the hip in 35 (45%), the elbow in 4 (5%), and the shoulder in 2 (3%) and were qualified as early in 31 patients (39.7%). Staphylococcus spp. were the most common pathogens accounting for 72.1% of the total number of bacterial strains identified. All included patients had surgery which consisted in debridement and implant retention in 59 of them (75.6%). Doxycycline and minocycline were prescribed as SAT in 72 (92%) and 6 (8%) patients, respectively. Adverse events were reported in 14 patients (18%), leading to SAT discontinuation in 6 of them (8%). After a mean follow-up of 1020 ± 597 days, a total of 22 (28.2%) patients had failed including 3 cases (3.8%) with documented acquisition of tetracycline resistance in initial pathogen(s). CONCLUSIONS: Our results suggest that oral cyclines used as SAT in patients treated for PJI have an acceptable tolerability and effectiveness and appear to be a reasonable option in this setting.

A promising new test to detect Streptococcus pneumoniae urinary antigen.

BACKGROUND: Streptococcus pneumoniae is the main etiology of community-acquired pneumonia (CAP). A quick detection of urinary antigen helps in obtaining a documented result in case of Streptococcus pneumoniae CAP. METHODS: We compared the BinaxNOW®S. pneumoniae test with the new urinary antigen Sofia®S. pneumoniae FIA. We examined 133 urine samples. RESULTS: Of the 133 included and tested non-concentrated urine samples, BinaxNOW® and Sofia® tests yielded 122 and 113 negative results and 11 and 20 positive results, respectively. The overall agreement between the tests was good. CONCLUSION: This new test enabled the diagnosis of seven additional cases (7/133=5.2%). The improved detection with Sofia® may be due to the immunofluorescence method used by this new test as compared with the colorimetric method used by BinaxNOW®. Sofia® also offers the advantage of being connected to the laboratory information system (LIS) allowing an automated traceability.

Suppressive antibiotic therapy with oral doxycycline for Staphylococcus aureus prosthetic joint infection: a retrospective study of 39 patients.

The aim of this study was to describe the use of oral doxycycline as suppressive antibiotic therapy (SAT) in patients with Staphylococcus aureus periprosthetic (hip or knee) joint infections. The medical charts of all patients with surgical revisions for S. aureus hip or knee prosthetic joint infections (PJIs) who were given doxycycline-based SAT because of a high risk of failure of various origins were reviewed. Data regarding tolerability and effectiveness of doxycycline-based SAT were analysed. A total of 39 patients (mean age 66.1 ± 16.3 years) received doxycycline-base SAT in the period from January 2006 to January 2014. PJIs involved the hip in 23 patients (59.0%) and the knee in 16 (41.0%), and were qualified as early in 15 patients (38.5%). Methicillin-resistant S. aureus (MRSA) accounted for 22% of the total number of bacterial strains identified. All patients included in the study had surgery, which consisted of debridement and implant retention in 32 (82.1%). Adverse events likely attributable to SAT were reported in six patients (15.4%), leading to discontinuation of SAT in three (7.7%). A total of 29 patients (74.4%) remained event-free and 10 (25.6%) failed, including 8 (20.5%) relapses and 2 (5.1%) superinfections. Overall, 8 of the 10 failure cases were related to a doxycycline-susceptible pathogen. These results suggest that oral doxycycline used as SAT in patients treated for S. aureus hip or knee PJIs has an acceptable tolerability and effectiveness and appears to be a reasonable option in this setting.

A fatal endocarditis case due to an emerging bacterium: Moraxella nonliquefaciens.

Moraxella nonliquefaciens is a Gram-negative coccobacillus considered as a commensal organism from the upper respiratory tract, with low pathogenic potential. The phenotypical conventional identification is difficult and the matrix-assisted laser desorption/ionization time-of-flight technology has increased the resolution of identification of this bacterium. We report a fatal case of endocarditis due to M. nonliquefaciens whose identification was confirmed by 16S rRNA, and we review the literature on this pathogen in endocarditis.

Outcome of patients with streptococcal prosthetic joint infections with special reference to rifampicin combinations.

BACKGROUND: Outcome of patients with streptococcal prosthetic joint infections (PJIs) is not well known. METHODS: We performed a retrospective multicenter cohort study that involved patients with total hip/knee prosthetic joint (THP/TKP) infections due to Streptococcus spp. from 2001 through 2009. RESULTS: Ninety-five streptococcal PJI episodes (50 THP and 45 TKP) in 87 patients of mean age 69.1 ± 13.7 years met the inclusion criteria. In all, 55 out of 95 cases (57.9 %) were treated with debridement and retention of the infected implants with antibiotic therapy (DAIR). Rifampicin-combinations, including with levofloxacin, were used in 52 (54.7 %) and 28 (29.5 %) cases, respectively. After a mean follow-up period of 895 days (IQR: 395-1649), the remission rate was 70.5 % (67/95). Patients with PJIs due to S. agalactiae failed in the same proportion as in the other patients (10/37 (27.1 %) versus 19/58 (32.7 %); p = .55). In the univariate analysis, antibiotic monotherapy, DAIR, antibiotic treatments other than rifampicin-combinations, and TKP were all associated with a worse outcome. The only independent variable significantly associated with the patients' outcomes was the location of the prosthesis (i.e., hip versus knee) (OR = 0.19; 95 % CI 0.04-0.93; p value 0.04). CONCLUSIONS: The prognosis of streptococcal PJIs may not be as good as previously reported, especially for patients with an infected total knee arthroplasty. Rifampicin combinations, especially with levofloxacin, appear to be suitable antibiotic regimens for these patients.

Epidemiology of patients with MSSA versus MRSA infections of orthopedic implants: Retrospective study of 115 patients.

Factors that predict the occurrence of a surgical site infection due to methicillin-resistant Staphylococcus aureus (MRSA) are not well known; however this information could be used to modify the recommended antimicrobial prophylaxis. We carried out a retrospective study of S. aureus infections on orthopedic implants to determine: (1) whether epidemiological factors can be identified that predict a MRSA infection, (2) the impact of these factors as evidenced by the odds ratio (OR). HYPOTHESIS: Risk factors for a MRSA infection can be identified from a cohort of patients with S. aureus infections. MATERIALS AND METHODS: We identified 244 patients who experienced a S. aureus surgical site infection (SSI) in 2011-2012 documented by intraoperative sample collection. Of these 244 patients, those who had a previous SSI (n=44), those with a SSI but no orthopedic implant (n=80) or those who had the infection more than 1-year after the initial surgery (n=5) were excluded. This resulted in 115 patients (53 arthroplasty, 62 bone fixation) being analyzed for this study. There were 24 MRSA infections and 91 MSSA infections. The following factors were evaluated in bivariate and multifactorial analysis: age, sex, type of device (prosthesis/bone fixation), predisposition (diabetes, obesity, kidney failure), and environmental factors (hospitalization in intensive care unit within past 5 years, nursing home stay). RESULTS: Two factors were correlated with the occurrence of MRSA infections. (1) Nursing home patients had a higher rate of MRSA infections (67% vs. 18%, P=0.017) with an OR of 8.42 (95% CI: 1.06-66.43). (2) Patients who had undergone bone fixation had a lower rate of MRSA infections than patients who had undergone arthroplasty (13% vs. 30%, P=0.023), OR 0.11 (95% CI: 0.02-0.56). Although the sample size was too small to be statistically significant, all of the patients with kidney failure (n=4) had a MRSA infection. DISCUSSION: Since these MRSA infection risk factors are easy to identify, the antimicrobial prophylaxis could be adapted in these specific patient groups.

In vitro susceptibility to mecillinam of Escherichia coli strains isolated from the urine of pregnant women.

OBJECTIVES: Pivmecillinam is a safe beta-lactam for use in pregnancy. It has been widely used for the treatment of lower urinary tract infections (UTIs) in the Nordic countries where its efficacy, minor impact on the microbiota, and low level of resistance among the Escherichia coli strains have been proven. However, susceptibility data related to E. coli involved in asymptomatic bacteriuria and lower UTIs in pregnant women is lacking. We aimed to support the 2015 recommendations issued by the French Infectious Diseases Society (SPILF) on gestational UTI, with a particular focus on pivmecillinam. MATERIAL AND METHODS: Antimicrobial susceptibility testing was performed by 12 hospitals with a maternity department on 235 E. coli strains isolated from the urine of pregnant women. Susceptibility to mecillinam was tested by disk diffusion method using the 2015 recommendations of the antibiogram committee of the French microbiology society (CA-SFM). RESULTS: Global susceptibility to mecillinam was 86.4%. Susceptibility to mecillinam was 96.5% for strains susceptible to amoxicillin-clavulanic acid and 38.7% for resistant strains. All six extended-spectrum beta-lactamase-producing E. coli strains were susceptible to mecillinam. CONCLUSION: Given the efficacy and safety of pivmecillinam during pregnancy, it may be used for the documented treatment of asymptomatic bacteriuria and acute cystitis in pregnant women. It also represents an alternative for the treatment of multidrug-resistant bacterial infections.

Influence of daily dosage and frequency of administration of rifampicin-levofloxacin therapy on tolerance and effectiveness in 154 patients treated for prosthetic joint infections.

Data on the tolerance and effectiveness of rifampicin-levofloxacin combination therapy (RLCT) in patients treated for prosthetic joint infections (PJIs) according to daily dosage are lacking. A review of the clinical data from patients treated with RLCT for PJIs in a French referent center for PJIs was conducted. A total of 154 patients (75 F/79 M), with a median age of 64.1 years and median body weight of 83.1 kg, were included. The median daily dosages of rifampicin and levofloxacin were, respectively, 1,200 mg (range 300-2,100) and 750 mg (range 500-1,500), corresponding to a mean daily dose per kg of, respectively, 16.2 ± 4.3 mg/kg and 10.1 ± 3.0 mg/kg. After a mean follow-up period of 55.6 ± 27.1 months (range 24-236), 127 patients (82.5 %) were in remission. Adverse events attributable to rifampicin and levofloxacin were reported in 48 (31.2 %) and 13 (8.4 %) patients (p < 0.001), respectively. Patients who experienced rifampicin-related adverse events had been given higher rifampicin daily doses than the other patients (p = 0.04). The rifampicin daily dosage did not influence patient outcome and nor did the levofloxacin daily dosage on both tolerance and patient outcome. Our results suggest that adjusting rifampicin daily doses to the patient total body weight when combined with levofloxacin for the treatment of PJIs is associated with a poor tolerance. High daily doses of rifampicin (>600 mg) and levofloxacin (750 mg) do not improve patient outcome when compared to lower daily doses in this setting.

Unique blood culture for diagnosis of bloodstream infections in emergency departments: a prospective multicentre study.

Detection of microorganisms by blood cultures (BCs) is essential in managing patients with bacteraemia. Rather than the number of punctures, the volume of blood drawn is considered paramount in efficient and reliable detection of microorganisms. We performed a 1-year prospective multicentre study in adult emergency departments of three French university hospitals comparing two methods for BCs: a unique blood culture (UBC) collecting a large volume of blood (40 mL) and the standard method of multiple blood cultures (MBC). The performances of both methods for bacterial contamination and efficient microbial detection were compared, each patient serving as his own control. Amongst the 2314 patients included, three hundred were positive for pathogens (n=245) or contaminants (n=55). Out of the 245 patients, 11 were positive for pathogens by UBC but negative by MBC and seven negative by UBC but positive by MBC (p 0.480). In the subgroup of 137 patients with only two BCs, UBC was superior to MBC (p 0.044). Seven and 17 patients had contaminated BCs by UBC and MBC only, respectively (p 0.062). Considering the sums of pathogens missed and contaminants, UBC significantly outperformed MBC (p 0.045). Considering the complete picture of cost savings, efficient detection of microorganisms and decrease in contaminations, UBC offers an interesting alternative to MBC.

Bacterial epidemiology of osteoarticular infections in a referent center: 10-year study.

INTRODUCTION: Management of osteoarticular infections combines surgical treatment with antibiotic therapy. For some teams the immediate postoperative regimen requires at least partly wide-spectrum probabilistic treatment while waiting for the microbiological results. This protocol exposes the patient to the selection of resistant bacteria and the hospital unit to a modification of its bacterial ecology. The objective of this study was to retrospectively describe the microbial epidemiology of the Traumatology and Orthopaedics Department of the Lille University Hospital over 10 years (2002-2011). MATERIALS AND METHODS: The bacterial species isolated in culture of osteoarticular samples were listed, after removing any duplicates. The antibiotics retained for follow-up were those used in treatment of these infections as well as those recognized as markers of resistance. For Gram-positive species, the antibiotics considered were methicillin, rifampicin, fluoroquinolones, glycopeptides, and linezolid; for the Gram-negative species, cefotaxime, cefepime, imipenem, and fluoroquinolones were considered. RESULTS: Of the 5006 strains isolated between 2002 and 2011, Gram-positive cocci accounted for more than 71%; Staphylococcus aureus 27%, and coagulase-negative staphylococci (CoNS) 54%. Contrary to S. aureus, resistance to methicillin, fluoroquinolones, and teicoplanin significantly increased in CoNS, reaching 44%, 34%, and 22%, respectively, of the strains in 2011. The proportion of streptococcal and enterococcal infections remained stable, a mean 7.4% and 5.3%, respectively, per year. Enterobacteria (12.5% of the isolates) were producers of extended-spectrum beta-lactamase in 7.8% of the cases. Pseudomonas aeruginosa was involved in 3.6% of the infections, and 12% of the strains remained resistant to ceftazidime. Propionibacterium acnes accounted for 5.8% of the bacteria isolated and showed few antibiotic resistance problems. DISCUSSION: Stability in the distribution and the susceptibility of different bacterial species was noted over this 10-year period. Although the evolution of S. aureus resistance was favourable, the resistance of CoNS specially to methicillin and glycopeptides increased. LEVEL OF EVIDENCE: Level IV. Retrospective cohort study.

First case of cerebral abscess due to a novel Nocardia species in an immunocompromised patient.

We report the first case of cerebral abscess due to a novel species of Nocardia in a heart transplant patient and describe the antimicrobial susceptibility of this isolate. As our patient was intolerant to trimethoprim-sulfamethoxazole, we also discuss alternative therapeutic options in brain abscess due to Nocardia sp.